Upper critical magnetic field of KxFe2-ySe2 and Eu0.5K0.5Fe2As2 single crystals

作者：Gasparov, Vitaly A.^*; Audouard, A.; Drigo, L.; Rodigin, A. I.; Lin, C. T.; Liu, W. P.; Zhang, M.; Wang, A. F.; Chen, X. H.; Jeevan, H. S.; Maiwald, J.; Gegenwart, P.

来源：Physical Review B, 2013, 87(9): 094508.

DOI：10.1103/PhysRevB.87.094508

• SUPERCONDUCTIVITY
• BA0.68K0.32FE2AS2
• CS

The H-T phase diagrams of single crystalline electron-doped K0.83Fe1.83Se2 (KFS1), K0.8Fe2Se2 (KFS2) and hole-doped Eu0.5K0.5Fe2As2 (EKFA) have been deduced from tunnel diode oscillator-based contactless measurements in pulsed magnetic fields up to 57 T for the interplane (H parallel to c) and in-plane (H parallel to ab) directions. The temperature dependence of the upper critical magnetic field H-c2(T) relevant to EFKA is accounted for by Pauli model including an anisotropic Pauli paramagnetic contribution (mu H-B(p) = 114 T for H parallel to ab and 86 T for H parallel to c). This is also the case of KFS1 and KFS2 for H parallel to ab whereas a significant upward curvature, accounted for by a two-gap model, is observed for H parallel to c. Despite the presence of antiferromagnetic lattice order within the superconducting state of the studied compounds, no influence of magnetic ordering on the temperature dependence of H-c2(T) is observed. DOI: 10.1103/PhysRevB.87.094508

• 出版日期2013-3-15
• 单位中国科学技术大学